Anti-malarial activity and HS-SPME-GC-MS chemical profiling of Plinia cerrocampanensis leaf essential oil.

BACKGROUND: Plinia cerrocampanensis is an endemic plant of Panama. The leaf essential oil of this plant has shown antibacterial activity. However, anti-malarial activity and chemical profiling by HS-SPME-GC-MS of this essential oil have not been reported before. METHODS: Anti-malarial activity of the essential oil (EO) was evaluated in vitro against chloroquine-sensitive HB3 and chloroquine-resistant W2 strains of Plasmodium falciparum. Synergistic effect of chloroquine and the EO on parasite growth was evaluated by calculating the combination index. A methodology involving headspace solid phase microextraction and gas chromatography-mass spectrometry (HS-SPME-GC-MS) was developed to investigate the composition of Plinia cerrocampanensis EO. RESULTS: Plinia cerrocampanensis EO showed a high anti-malarial activity and a synergistic interaction with chloroquine. The Plinia cerrocampanensis EO inhibited P. falciparum growth in vitro at an IC50 of 7.3 µg/mL. Chloroquine together with the EO decreased the IC50 of chloroquine from 0.1 µg/mL to 0.05 µg/mL, and of the EO from 7.3 µg/mL to 1.1 µg/mL. The measured combination index was 0.58, which clearly indicates that the EO acts synergistically with chloroquine. Since the EO maintained its inhibitory activity on the chloroquine-sensitive strain of the parasite, it could be acting by a different mechanism of action than chloroquine. The best HS-SPME-GC-MS analytical conditions were obtained when the temperature of extraction was 49°C, incubation time 14 min, and the time of extraction 10 min. This method allowed for the identification of 53 volatile constituents in the EO, including new compounds not reported earlier. CONCLUSIONS: The anti-malarial activity exhibited by the Plinia cerrocampanensis EO may lend support for its possible use as an alternative for anti-malarial therapy.

Polyphenols as therapeutic molecules in Alzheimer's disease through modulating amyloid pathways.

Alzheimer's disease (AD) is a complex and multifactorial neurodegenerative condition. The complex pathology of this disease includes oxidative stress, metal deposition, formation of aggregates of amyloid and tau, enhanced immune responses, and disturbances in cholinesterase. Drugs targeted toward reduction of amyloidal load have been discovered, but there is no effective pharmacological treatment for combating the disease so far. Natural products have become an important avenue for drug discovery research. Polyphenols are natural products that have been shown to be effective in the modulation of the type of neurodegenerative changes seen in AD, suggesting a possible therapeutic role. The present review focuses on the chemistry of polyphenols and their role in modulating amyloid precursor protein (APP) processing. We also provide new hypotheses on how these therapeutic molecules may modulate APP processing, prevent Aß aggregation, and favor disruption of preformed fibrils. Finally, the role of polyphenols in modulating Alzheimer's pathology is discussed.

Antioxidant activity and polyphenol content in cultivated and wild edible fruits grown in Panama.

OBJECTIVES: The present research was undertaken to determine the antioxidant activity and total polyphenol content of cultivated and wild edible fruits consumed in Panama. MATERIALS AND METHODS: 39 cultivated and wild edible fruits antioxidant activity and total polyphenol content was assessed by using the DPPH and the Folin-Ciocalteu assays, respectively. RESULTS AND DISCUSSION: The antioxidant composition of the fruits varied between 1083.33 and 16.22 mg TEAC/100 g fresh weight. On the other hand, the total phenolic content of the 39 fruits tested ranged from 604.80 to 35.10 mg GAE/100 g FW. Ziziphus mauritania presented the highest antioxidant activity and the largest phenolic content, whereas most fruits had a moderate TEAC value. CONCLUSION: Fruits polyphenol content was strongly correlated with antioxidant properties, which pointed out the important role of these compounds in the prevention of many types of cancer, neurological ailments, and cardiovascular diseases through diverse antioxidant mechanisms.